Safety casing head for oil wells



13, 1931- M. s. CUNNINGHAM. 1,819,875

SAFETY CASING HEAD FOR OIL WELLS Filed May 24, 1930 INVENTOR.

BY I

A TTORNE Y.

Patented Aug. 18, 1931 MARION STOKES CUNNINGHAM, E DALLAS, TEXAS snrn'ry casino HEAD non on. wEnLs Application filed Kay 24, 1930. Serial No. 455,181.

My invention relates to oil well equipment and more particularly to a safety casing head for shutting oil the flow of oil wells.

The primary object of my invention consists of means in combination with a casing head and oil well casing whereby the oil well when brought in may be quickly shut off, particularly in wild wells, and the oil or gas or Ofi quantities of oil or gas after the casing head has been removed.

With the above'objects in view my invention will be better understood from' a perusal of the following detailed description,

taken in connection with the accompanying drawings and. wherein: p

Figure 1 represents a side elevational view of an oil well casing head and embodying my invention, the view being partly sectioned and partly broken away.

Figure 2 is a top plan view thereof. Figure 3 is a cross sectional view in part, the view being taken along the line 33 in Figure 2; and

Figures 4 and 5 are, respectively, a detail top plan View and a side elevational View of the valve arrangement for closing the well when the tools are in the hole.

Having a more detailed reference to the drawings, 1 denotes a casing head with vertical and horizontal, passages and including "the annular flanged parts 2 and 3. Gennected to opposite sides of the casing head and to the-parts 2 are cylinders 4 and 5 and 1 within these cylinders are disposed reciproeating members in the form of the pistons 6 and Each of the cylinders are provided jfsteam inlet ports where there is secured 8 and exhaust ports wherein there are sensed short pi es 9 with valves 10. The steam is supphe to the cylinders at a point remote from the well and moves the pistons 6 and 7 inwardly the air being exhausted through the pipes 9. a

In Figure 2 it will be observed that the easing head interior is constructed with longitudinal ledges 11 for the purpose of supporting each of the valve members carried on the piston rods 12. These valve members are shown more clearly in Figs. 3, 4 and 5, and are connected to a prolongation 13 of the piston rods 12. Each member is provided with a semicircular'opening or recess as at 15 for snugly engaging the periphery of the drill rod indicated at 17, the member 18 being relatively fiat and being formed integrally with a disk-like part 19. The part 19 is recessed on opposite sides so that it Will support the valve member upon the ledge in a slidable manner in the operation of the closing and opening operation of themembers These recessed portions are indicated at 20, in Figures 3 and 5, and likewise the ledges 11 are provided with a longitudinal slot 21 in which the side-edges of the valve members slide. Packing nuts 22 are provided at each end of the cylinders 4 and 5. In order that each of the valve members may operate in unison with its mate, the "construction includes links 24 in pairs at each slide of the cylinders, The outer ends of these links are pivoted to cross bars 25 by means of the bolts 26, the bar having a connection to the piston rods as at 26 while the inner ends of the links are pivoted at 28 to a centrally pivoted bar 30 connected to the casing head by the members 31.

Spaced below and connected to the lower end of the casing head is a section of cylindrical formation 32 with a rolongation 33 and connected to the latter is a cylinder 35. This cylinder carries a piston (not shown) with rod on which is carried a standard gate valve (also not shown) for closing the casing A when the tools are removed from the well. A' steam pipe 36 connects to the cylinder 35 and supplies steam for closing the valve. when requlred.

1 There is also provided means for drawlng Mi quantities of oil or gas when desired which consists of a pipe 39 and a cylinder 38. This cylinder carries a piston and rod 40 and 41 and'a valve (not shown) carriedon the rod and operating under steam pressure from the pipe 43 closes the valve.

From the foregoing itwill be apparent that when steam is applied to the pistons 6 and 7, and the valves 10 opened, the valve members 18 will be closedjsnugly around the drill stem-17 as clearly shown in Figure 4: and in Figure? which will efiectually cut ofi any oil or gas flow. When desirous of removing the'tools, steam'is admitted throu h the valves 10 the exhaust being through t e pipes 18 which areopened and the valve members advanced from the drill rod. After removal of the tools, the valve operated by the piston in the cylinder 35 is o erated and quantities 0 liquid to close the casin or gas drawnofi y opening the lowermost valve operable by the piston 40.

What is claimed as new is: 1

A safety casing head vfor controlling oil wells, said head formed with vertical and horizontal passages, a cylinder connected to each end of the horizontal passages, pistons and rods in each cylinder;-the interior of the cylinders and the interior of the horizontal passages being of substantially the same diameter; a valve member carried by each of the piston rods, said valve member'comprising a disk-like formation for fitting snugly the interior walls of the horizontal passa es of the head and including a relatively at body portion for engaging one half of a drill rod, longitudinal ledges formed on opposit'e sides of the interior walls of the horis zontal passages of the head; longitudinal ooves in the peripheries of the disk-like ormation and adapted to permit the latter to slide over the ledges to guide the valve members to and from engagement with the drill rod; and means in the cylinders for pressure on introducing steam or similar each side of the pistons.

In testimony whereof I afiix my signature. MARION STOKES CUNNINGHAM. I 

